Easy Musical Variations
The variations discussed here might also be known as arpeggios or vamping or broken chords. Synthesizers or such often offer arpeggio features, though one can also use a permutation algorithm to go through them all, possibly filtering for particular aspects.
One aspect would be to preserve a particular note, for example to "stand on the tonic" or some other scale degree. The dominant is popular, especially in certain Sonata forms, maybe to extend the half cadence for some number of measures. A half cadence is some motion to the dominant, which will feel unresolved, and in certain Sonata forms will usually be followed by a phrase that ends with a perfect cadence, for that full sense of completion. Anyways, permutations. The easiest method these days is probably to find a library and write some glue code.
This can then be played around with, like what if we want all the permutations, but never to repeat the same note twice?
Or what if we drop the entire permutation if the starting note is the same as the last note played?
These could then be used as phrases, or be built up with other instruments, subsections of them reworked, etc.
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